Tehran University Medical Journal

Background: Over the last two decades invasive candidiasis has become an increasing problem in neonatal intensive care units (NICUs). Colonization of skin and mucous membranes with Candida spp. is important factor in the pathogenesis of neonatal infection and several colonized sites are major risk factors evoking higher frequencies of progression to invasive candidiasis. The aim of this study was to detect Candida colonization in NICU patients.

Methods: This cross-sectional study was conducted on 93 neonates in NICUs at Imam Khomeini and Children Medical Center Hospitals in Tehran. Cutaneous and mucous membrane samples obtained at first, third, and seventh days of patients’ stay in NICUs during nine months from August 2013 to May 2014. The samples were primarily cultured on CHROMagar Candida medium. The cultured media were incubated at 35°C for 48h and evaluated based on colony color produced on CHROMagar Candida. In addition, isolated colonies were cultured on Corn Meal Agar medium supplemented with tween 80 for identification of Candida spp. based on their morphology. Finally, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was performed for definite identification of isolated species.

Results: Colonization by Candida spp. was occurred in 20.43% of neonates. Fifteen and four patients colonized with one and two different Candida spp., respectively. Isolated Candida spp. identified as; C. parapsilosis (n: 10), C. albicans (n: 7), C. tropicalis (n: 3), C. guilliermondii (n: 2), and C. krusei (n: 1). In present study non-albicans Candia species were dominant (69.56%) and C. parapsilosis was the most frequent isolate (43.47%). Using Fisher's exact test, the correlation between fungal colonization with low birth weight, low gestational age, and duration of hospital stay was found to be statistically significant (P=0.003).

Conclusion: The results of this study imply to the candida species colonization of neonates. Neonates in NICU are at the highest risk for severe infection with Candida parapsilosis. Therefore, isolation of C. parapsilosis as the most common species (43.47%) in present study was noteworthy.

Background: Bacterial sepsis is a main cause of mortality and morbidity especially in preterm newborns. The aim of this study was to search the bacterial etiologies of neonatal sepsis in NICU admitted preterm neonates.

Methods: A descriptive cross-sectional study had done in NICU of Ali Asghar Hospital, Tehran, Iran from March 2007 to March 2009. Seventy septicemic preterm newborns (<37 weeks) were studied. At admission day, for blood culture, 1-2 ml of venous blood was drawn after swabbing the venipuncture site with alcohol. After centrifugation of blood samples, deposits were cultured on sheep blood agar and incubated in a candle jar at 37 °C for 48 h and followed by subcultured. Isolates were identified using standard techniques (Nima pouyesh, Iran). Type of isolated bacterial organisms determined. Its correlation with gestational age, birth weight, premature rupture of membranes (PROM) and other variables determined we used the nonparametric two independent sample test, Mann-Whitney U test. Chi-square values (CI 95%, P< 0.05) were calculated for all categorical variables. P-value less than 0.05 considered statistically significant.

Results: Of 70 studied septicemic preterm cases, 17 (10.6%) cases had positive blood culture. Overall gram-negative organisms were more frequent than gram-positive organisms, Klebsiella (K.) pneumoniae, Escherichia (E.) coli and Staphylococcus (S.) aureus organisms were the 3 common causes of bacterial sepsis in studied cases. Early onset sepsis produced by K. pneumonia (40%), E. coli (20%) and S. aureus (20%). K. pneumonia, E. coli, S. aureus had equal incidence in late onset sepsis (26.8%). K. pneumonia was more frequent in early onset sepsis (P= 0.05), and in low birth weight (< 1500 g) neonates (P= 0.005, and PROM (P= 0.05).